FWW... whats next?

[ComradeP]

Most status effects have a binary nature in the game: they either apply, or they don't. They don't slowly build up to a certain point, nor do they have extents to which they apply/stages scaling up.

Fatigue is one of the two values (the others being manpower strength) with a "regular" numerical value attached to it.

Quality, though represented as a letter, is technically also a number when used in calculations, but it isn't represented as such and it doesn't fluctuate to the same extent as fatigue or manpower strength. The maximum number of available movement points fluctuate based on other conditions or states applied to them, not directly through combat operations.

Fatigue  for combining units could thus be fixed fairly easily by averaging the fatigue value, just like manpower is averaged when combining and decombining units. However, this isn't entirely without problems: though you're right that a wrecked company wouldn't drag down the entire battalion along with it, it's also strange that a wrecked company in an abstracted sense swaps platoons with fresh(er) companies so it recovers men and readiness. That's not how a military formation works, as it throws cohesion, organization and unit hierarchy out of the window.

It's also, for obvious reasons, only a problem for the side that can (de)combine units, which for Eastern Front titles is usually just the Germans for infantry units. In Moscow '42, the Germans have 4 company battalions to make decombining less punishing in terms of fatigue gain. Other sides would mostly notice it when (de)combining vehicle units.

For all other status effects, from Disrupted to using mixed quality units in an assault, the worst unit still degrades the capabilities of the entire battalion/stack when combining or attacking.